Anterior Compartment Of The Forearm: Origins And Insertions

Front 1

Pronator Teres: Humeral Head

Back 1

O: proximal to the medial epicondyle

I: antero/lateral surface of the mid-point of the radius

Front 2

Pronator Teres: Ulnar Head

Back 2

O: coronoid process of the ulna

I: antero/lateral surface of the mid-point of the radius

Front 3

Flexor Carpi Radialis

Back 3

O: medial humeral epicondyle (common flexor mass)

I: ventral surface, base of the 2nd metacarpal (possibly a slip to the 3rd metacarpal)

Front 4

Palmaris Longus

Back 4

O: medial humeral epicondyle (common flexor mass)

I: palmar aponeurosis

Front 5

Flexor Carpi Ulnaris: Humeral Head

Back 5

O: medial humeral epicondyle (common flexor mass)

I: directly into the pisiform
into the hamate (piso-hamate ligament)
into the ventral surface of the base of the 5th metacarpal (piso-metacarpal ligament)

Front 6

Flexor Carpi Ulnaris: Ulnar Head

Back 6

O: proximal portion of the subcutaneous border of the ulna

I: directly into the pisiform
into the hamate (piso-hamate ligament)
into the ventral surface of the base of the 5th metacarpal (piso-metacarpal ligament)

Front 7

Flexor Digitorum Superficialis: Humeral Head

Back 7

O: medial humeral epicondyle (common flexor mass)

I: middle phalanx of digits 2-5, via split/sling tendon

Front 8

Flexor Digitorum Superficialis: Ulnar Head

Back 8

O: base of the coronoid process of the ulna

I: middle phalanx of digits 2-5, via split/sling tendon

Front 9

Flexor Digitorum Superficialis: Radial Head

Back 9

O: ventral surface, proximal 1/3 of radius

I: middle phalanx of digits 2-5, via split/sling tendon

Front 10

Flexor Pollicis Longus

Back 10

O: ventral surface, middle 1/3-1/2 of radius and interosseous membrane

I: distal phalanx of thumb

Front 11

Flexor Digitorum Profundus

Back 11

O: medial and ventral surfaces of the proximal 1/2-1/3 of the ulna and adjacent interosseous membrane

I: base of the distal phalanx of digits 2-5

Front 12

Flexor Digitorum Profundus Lumbricales

Back 12

O: from the tendons of the flexor digitorum profundus
#1 - from the radial side of the tendon to the index finger
#2 - from the radial side of the tendon to the middle finger
#3 & #4 - from both tendons

I: radial side of extensor expansion of digits 2-5

Front 13

Pronator Quadratus

Back 13

O: ventral surface, distal 1/8-1/4 of the ulna

I: ventral surface, distal 1/8-1/4 of the radius

Front 14

Abductor Pollicis Brevis

Back 14

O: flexor retinaculum and trapezium

I: proximal phalanx of thumb, radial side

Front 15

Flexor Pollicis Brevis: Superficial Head

Back 15

O: flexor retinaculum and trapezium

I: base of the proximal phalanx of thumb, radial side

Front 16

Flexor Pollicis Brevis: Deep Head

Back 16

O: floor of the carpal canal/tunnel

I: base of the proximal phalanx of thumb, radial side

Front 17

Opponens Pollicis

Back 17

O: flexor retinaculum and trapezium

I: radial surface of 1st metacarpal

Front 18

Adductor Pollicis: Transverse Head

Back 18

O: shaft of the 3rd metacarpal, ventral surface

I: base of proximal phalanx of thumb, ulnar side

Front 19

Adductor Pollicis: Oblique Head

Back 19

O: base of metacarpals 1, 2, & 3 and floor of the carpal tunnel

I: base of proximal phalanx of thumb, ulnar side

Front 20

Abductor Digiti Minimi

Back 20

O: pisiform and piso-metacarpal ligament

I: ulnar aspect, proximal phalanx of 5th digit

Front 21

Flexor Digiti Minimi (Brevis)

Back 21

O: flexor retinaculum and hook of hamate

I: ulnar aspect, proximal phalanx of 5th digit

Front 22

Opponens Digiti Minimi

Back 22

O: flexor retinaculum and hook of hamate

I: ulnar border, shaft of 5th metacarpal

Front 23

Palmar Interossei

Back 23

O: #1 - ulnar surface, shaft of 2nd metacarpal
#2 - radial surface, shaft of 4th metacarpal
#3 - radial surface, shaft of 5th metacarpal

I: extensor expansion of respective digit

Front 24

Dorsal Interossei

Back 24

O: #1 - from adjacent sides of metacarpals 1&2
#2 - from adjacent sides of metacarpals 2&3
#3 - from adjacent sides of metacarpals 3&4
#4 - from adjacent sides of metacarpals 4&5

I: base of proximal phalanx and extensor expansion of respective digits